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101.
目的:分析肺心病合并脑梗死的临床特点.方法:对39例肺心病合并脑梗死患者的临床资料进行回顾性分析.结果:肺心病合并脑梗死发病率6.2%,48小时内确诊率48.7%.结论:肺心病合并脑梗死临床表现不典型,及时确诊困难. 相似文献
102.
目的观察比较泼尼松联用硫唑嘌呤和大剂量静脉用免疫球蛋白(IVIG)对扩张型心肌病(DCM)患儿心功能及预后的影响。方法将DCM患儿20例分为治疗Ⅰ和Ⅱ组,分别在传统抗心衰治疗基础上加泼尼松联用硫唑嘌呤和大剂量IVIG,治疗1个疗程后评价心功能,检测治疗前后左房横径(LA)、左室舒张期内径(LV)、左室射血分数(LVEF)、心脏指数(CI),并计算其治疗前后变化。所有病例随访1年,计算1年存活率。结果治疗Ⅱ组心功能明显优于治疗Ⅰ组(P均<0.05);两组LA、LV、LVEF和CI治疗后较治疗前均有明显改善(P均<0.05);治疗Ⅰ组各参数变化明显低于治疗Ⅱ组(P均<0.05),其1年存活率明显低于治疗组Ⅱ(P<0.05)。结论泼尼松联用硫唑嘌呤和大剂量IVIG均能改善DCM患儿心功能,但IVIG疗效优于泼尼松联用硫唑嘌呤。 相似文献
103.
Sufentanil and vecuronium are commonly used simultaneously in anaesthesia. Bradycardia and asystole have been described immediately after the administration of these two compounds. Therefore, the purpose of the present study was to evaluate the direct cardiac effects of sufentanil and vecuronium in all parts of the cardiac pacemaker and conduction system.
The electrophysiological effects of sufentanil and vecuronium were studied in isolated spontaneously beating guinea-pig hearts perfused by the method of Langendorff. At a concentration of 0.1 μmol/1 sufentanil a significant reduction of the spontaneous sinus rate, prolongation of atrioventricular, intraventricular and His' bundle conduction could be observed. The highest concentration of 10 μmol/1 of sufentanil led to an overall slowing of conduction velocity and to an profound slowing of spontaneous sinus rate. AV nodal as well as atrial and ventricular refractoriness were markedly prolonged at this high concentration of sufentanil. In contrast, during perfusion with vecuronium at a concentration of 0.1 μmol/1 up to 10 μmol/1 no significant effects on cardiac conduction and pacemaker activity could be observed.
In conclusion, the electrophysiological effects of sufentanil are comparable to that of unspecific calcium antagonists. Therefore, especially in patients with a preexisting damage of the cardiac conduction system, the indirect effect of the combination of sufentanil and vecuronium which is predominantly responsible for bradycardia and asystole may be worsened by the direct effects of sufentanil. 相似文献
The electrophysiological effects of sufentanil and vecuronium were studied in isolated spontaneously beating guinea-pig hearts perfused by the method of Langendorff. At a concentration of 0.1 μmol/1 sufentanil a significant reduction of the spontaneous sinus rate, prolongation of atrioventricular, intraventricular and His' bundle conduction could be observed. The highest concentration of 10 μmol/1 of sufentanil led to an overall slowing of conduction velocity and to an profound slowing of spontaneous sinus rate. AV nodal as well as atrial and ventricular refractoriness were markedly prolonged at this high concentration of sufentanil. In contrast, during perfusion with vecuronium at a concentration of 0.1 μmol/1 up to 10 μmol/1 no significant effects on cardiac conduction and pacemaker activity could be observed.
In conclusion, the electrophysiological effects of sufentanil are comparable to that of unspecific calcium antagonists. Therefore, especially in patients with a preexisting damage of the cardiac conduction system, the indirect effect of the combination of sufentanil and vecuronium which is predominantly responsible for bradycardia and asystole may be worsened by the direct effects of sufentanil. 相似文献
104.
四氧嘧啶诱发糖尿病大鼠血管紧张素的变化 总被引:1,自引:0,他引:1
实验观察了四氧嘧啶诱发糖尿病大鼠连续饲养110d后体内肾素一血管紧张素系统的变化。结果表明,血浆和心脏的血管紧张素Ⅱ含量无明显变化,而肾脏的AngⅡ含量却明显低于正常对照组。另外,心脏的心钠素(ANP)含量在糖尿病大鼠与正常对照组之间无差别,血中的糖化血红蛋白含量基本无变化。上述结果表明,糖尿病大鼠早期心脏可能无明显损伤,而肾脏的肾素一血管紧张素系统活性降低。 相似文献
105.
Abstract: A pulsatile impeller assist heart and a total heart were tested as a chronic left ventricular assist device in 5 calves and an acute biventricular assist device in 4 pigs respectively, to evaluate their blood compatibility. During the left ventricular assist experiments, the indicators for hemolysis, thrombogenesis, renal dysfunction, and hepatic dysfunction were measured preoperatively, at the beginning of the pumping, 6 h postoperatively, and every following day. The results demonstrated that the impeller assist heart causes no severe blood damage nor organ dysfunction in the experiments lasting up to 11 days. In biventricular assist experiments, the number of red blood cells, white blood cells, platelets, and the he-matocrit, hemoglobin, free hemoglobin, and lactate dehy-drogenase levels were tested preoperatively at the beginning of the pumping and every 2 h postoperatively. The data remained in acceptable ranges during experiments lasting 6 h. It is confirmed that the authors' impeller assist heart and total heart have the advantages of simplicity, implantability, and pulsatility with good blood compatibility. 相似文献
106.
Abstract: A prospective study was performed to determine whether low-density lipoprotein (LDL) apheresis, when performed only immediately before and after percutaneous transluminal coronary angioplasty (PTCA), is effective in preventing restenosis of coronary artery lesions following PTCA. Thirty-six patients with coronary heart disease (CHD) and hypercholesterolemia were divided into 2 groups. The 9 patients in the LDL group underwent LDL-apheresis 1 day before and 5 days after PTCA while the 27 patients of the control group underwent PTCA but did not undergo LDL-apheresis. Follow-up coronary angiography (CAG) was performed 4 months after PTCA. The rate of restenosis of coronary artery lesions was significantly lower in the LDL group (0%) than in the control group (30%). These findings suggest that LDL-apheresis, when performed before and after PTCA, is effective in preventing restenosis of coronary artery lesions in patients with CHD and hypercholesterolemia. 相似文献
107.
Shelley A. Klemm Richard D. Gordon Terry J. Tunny Wendy L. Finn 《Clinical and experimental pharmacology & physiology》1990,17(3):191-195
1. Plasma potassium and chloride concentrations were raised and plasma renin activity, aldosterone, bicarbonate and arterial pH were reduced in two brothers with the syndrome of hypertension and hyperkalaemia with normal glomerular filtration rate (Gordon's syndrome), on unrestricted or moderately restricted sodium diets. 2. These abnormalities were corrected in both patients within 10 days of severe sodium restriction. 3. Pressor sensitivity to cold and angiotensin II decreased on low sodium diet, associated with a fall in blood pressure. 4. Increasing distal tubular sodium delivery by infusion of normal saline increased fractional excretion of potassium when aldosterone had been stimulated by severely restricted sodium diet, but not when aldosterone levels were low on unrestricted sodium diet. 5. These findings are consistent with excessive sodium reabsorption as the primary renal lesion in Gordon's syndrome, leading to volume expansion and suppression of renin and aldosterone. Severe dietary sodium restriction leading to volume contraction, by stimulating renin and aldosterone and promoting kaliuresis, corrects the abnormalities. 相似文献
108.
BERNHARD FREY MICHAEL WUTTE RUDOLF BERGER CLEANTHIS IOANNIDES MARTIN HÜLSMANN BRIGITTE STANEK RICHARD PACKER 《Pacing and clinical electrophysiology : PACE》1995,18(1):152-158
To investigate the impact of staged therapy for advanced heart failure on therapeutic endpoints, 236 consecutive patients (coronary artery disease/dilated cardiomyopathy in 61/175 patients, left ventricular ejection fraction 14%± 5%, New York Heart Association Class IIl/IIIIV in 102/79/55 patients, respectively) with advanced heart failure were prospectively followed. One hundred thirtyseven patients enrolled from January 1989 to December 1991 were treated conventionally with digoxin, furosemide, and low dose angiotension converting enzyme (ACE) inhibition. Patients refractory to this therapy underwent urgent heart transplantation. Ninetynine patients enrolled from January 1992 to August 1993 underwent staged therapy: stage 1: maximal tolerated ACE inhibition; stage 2: therapy with PGE1 for preand afterload reduction to achieve hemodynamic stabilization; or stage 3: refractory patients bridged to heart transplantation with continuous outpatient dobutamine. Sudden death was defined as death within 1 hour of symptoms if heart failure symptoms remained stable over the previous 7 days. Conventionally treated patients were followed for 10 ± 9 months; patients who underwent staged therapy for 9 ±5 months. In the group of patients that underwent standard therapy, 39 of 137 (28%) patients died: 5 (13%) deaths occurred suddenly, and death due to progressive pump failure occurred in the remaining 34 (87%) patients. In the group of patients that underwent staged therapy, 25 of 99 (25%) patients died: 13 (52%) deaths occurred suddenly, and 12 (48%) deaths occurred due to progressive pump failure. Thus, patients who underwent staged therapy were at increased risk for sudden death (P = 0.01, relative risk 3.4, 95% confidence interval 1.2–9.7) but were at lower risk for death from pump failure (P = 0.009, relative risk 0.44, 95% confidence interval 0.22–0.84). In patients who underwent therapy with continuous outpatient PGE1 (n = 7) or dobutamine (n= 21), risk for sudden death (P = NS by log rank test) did not increase. In conclusion, staged therapy significantly reduced death from pump failure; however, patients who could be stabilized and considered too well for heart transplantation were at increased risk for sudden death. Thus, overall survival did not improve. Of note, outpatient dobutamine did not increase the risk for sudden death. 相似文献
109.
HEINER LANGENFELD AXEL KREIN MICHAEL KIRSTEIN LUDWIG BINNER† EUROPEAN PEA CLINICAL INVESTIGATION GROUP 《Pacing and clinical electrophysiology : PACE》1998,21(11):2187-2191
The peak endocardial acceleration (PEA, unit g) shows a near correlation with myocardial contractility during the isometric systolic contraction of the heart (dP/dtmax), with sympathetic activity and, thus, with physiological heart rate modulation. The (Biomechanical Endocardial Sorin Transducer (BEST) sensor is incorporated in the tip of a pacing lead and measures PEA directly near the myocardium. In an international study, the lead was implanted with the dual chamber pacemaker Living-1 (Sorin) in 105 patients. The behavior of the PEA signal was tested under conditions of physical and mental stress and during daily life activities by 24-hour recordings of PEA (PEA Holter) at 1 to 2 months and approximately 1 year after implantation. Implantation of the BEST lead was performed without complications in all patients. The sensor functioned properly in the short- and long-term in 98% of patients. Although PEA values differed from patient to patient, the values closely reflected the variations in sympathetic activity due to physical and mental stress in each patient. During exercise and during daily life activities a close correlation between PEA and heart rate was observed among patients with normal sinus rhythm. Peak endocardial acceleration allows a nearly physiological control of the pacing rate. 相似文献
110.
目的了解临床标本中主要致病菌分布及敏感性分析,指导抗生素的选择及合理治疗方法对我院1994~1996年临床分离的1870株细菌的分布及敏感性、耐药性进行分析,1996年与1994年的结果进行比较,并将1995年的结果与北京地区5家教学医院同年的结果进行比较。结果分离菌株主要分布于呼吸道、消化道、泌尿道、血液及骨髓。G+菌占10.5%,G-菌占89.5%,占明显优势。沙门氏菌对头孢唑啉和哌拉西林的耐药性明显降低(P<0.01),大肠埃希氏菌对氨苄西林和氟嗪酸的耐药性明显增高(P<0.01),其余菌株无明显差异。抗生素敏感性覆盖率最高的是复达欣,其次为丁胺卡那,最低者氨苄西林。大肠埃希氏菌、假单胞菌对哌拉西林的耐药率,克雷伯杆菌属对西力欣的耐药率,肠肝菌属对哌拉西林的耐药率均高于北京地区。结论本组资料显示不断监测和分析菌丛的变化及对不同抗生素耐药性出现的频率和耐药谱至关重要。 相似文献